Method and system for evaluating brightness values in sensor images of image-evaluating adaptive cruise control systems

• US 8,373,754 B2
• Filed: 08/28/2008
• Issued: 02/12/2013
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Valeo Schalter und Sensoren GmbH (Valeo SE)
• Original Assignee: Valeo Schalter und Sensoren GmbH (Valeo SE)
• Inventors: Kuehnle, Andreas, Boon, Cathy
• Primary Examiner(s): Avellino, Joseph
• Assistant Examiner(s): KHAN, AFTAB N
• Application Number:
  US12/673,666
• Publication Number:
  US 20110109743A1
• Time in Patent Office: 1,629 Days
• Field of Search: 348/142, 348/143, 348/148, 348/149, 348/658, 348/E3.018, 382/195, 382/224
• US Class Current: 348/148
• CPC Class Codes: G06V 20/58 Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads

Abstract

A method and an arrangement for evaluating sensor images of an image-evaluating surroundings-detection system on a moved carrier, preferably a vehicle (1), are proposed, wherein areas in the sensor images captured by a camera (4) which are dark in relation to the surroundings are evaluated in chronologically successive evaluation steps in order to determine whether said dark areas are moving toward the carrier at the speed of said carrier, and in that these dark areas are detected as shadows (7) of a static object and corresponding signaling is performed.

Claims

1. A method for evaluating sensor images of an image-evaluating surroundings-detection system on a moving carrier, wherein the carrier has a driver assistance system, comprising:

evaluating captured sensor images which are dark in relation to the surroundings in chronologically successive evaluation steps;

determining whether said dark images are moving toward the carrier at a speed of said carrier;

wherein the dark images are detected as shadows of a static object and corresponding signaling is performed, and

wherein the driver assistance system comprises a lane-keeping assistance system, and

evaluating a series or an area of pixels of the sensor image in terms of a distance from the carrier of the image-evaluating surroundings-detection system,

wherein the series or the area of pixels of the sensor image comprise one selected from the dark images or one selected from a set of captured sensor images that are bright in relation to the surroundings,

wherein the series or the area of pixels which are dark or bright in relation to the surroundings are evaluated in chronologically successive evaluation steps to determine whether, and at what time intervals, the pixels are successively congruent with captured areas (ROI), defined in a direction of the carrier, within the sensor image, and

wherein the captured areas (ROI) comprise 80% of pixels with a brightness value below a predefined threshold and 20% of pixels with the brightness value above the predefined threshold.

2. The method as claimed in claim 1, wherein congruence with a captured area is detected when a relatively large number of the pixels of the captured area (ROI) have a brightness value (L) below a predefined first threshold.

3. The method as claimed in claim 1, wherein exiting from the captured areas is detected when a relatively small number of the pixels of the captured area (ROI) have a brightness value (L) above a predefined second threshold.

4. The method as claimed in claim 1, wherein the evaluation of a series or an area of pixels in a predefined time period is performed using a parameter distribution algorithm, before automatic illumination control and sensitivity control of the surroundings-detection system and of the camera is carried out.

5. The method as claimed in claim 4, further comprising:

detecting exiting from a captured area (ROI) when the illumination control of the surroundings-detection system in the captured area (ROI) assumes a constant profile over a predefined time period.

6. A computer program product stored on a non-transitory computer readable medium, comprising computer-readable programming instructions which, when the computer program product is executed on a microprocessor with associated storage means, cause the microprocessor to carry out a method as claimed in claim 1.

7. An arrangement for evaluating sensor images of an image-evaluating surroundings-detection system on a moving carrier, comprising:

an electronic camera of the image-evaluating surroundings-detection system which is mounted on a vehicle as a carrier, wherein the camera is configured to continuously capture an area of the vehicle which is at the front in a direction of travel on a roadway

wherein, in each case, a sensor image comprising pixels and whose brightness values and color values depict the surroundings is present,

an evaluation unit configured to;

detect dark areas in the sensor image of the camera as shadows of a static object, and configured to perform corresponding signaling based on the detected dark areas,

evaluate a series or an area of pixels of the sensor image in terms of a distance from the carrier of the image-evaluating surroundings-detection system,

wherein the series or the area of pixels of the sensor image comprise one selected from the dark images or one selected from a set of captured sensor images that are bright in relation to the surroundings,

wherein the series or the area of pixels which are dark or bright in relation to the surroundings are evaluated in chronologically successive evaluation steps to determine whether, and at what time intervals, the pixels are successively congruent with captured areas (ROI), defined in a direction of the carrier, within the sensor image, and

wherein the captured areas (ROI) comprise 80% of pixels with a brightness value below a predefined threshold and 20% of pixels with the brightness value above the predefined threshold

wherein the vehicle has a driver assistance system comprising a lane-keeping assistance system.

8. The arrangement as claimed in claim 7, wherein the color values of the color blue are utilized through indirect illumination by sunlight.

9. The arrangement as claimed in claim 7, wherein the evaluation unit is additionally supplied with a speed of the vehicle.

10. The arrangement as claimed in claim 7, wherein the signaling is displayed using a display unit in which the detection of the shadow, the exiting of the shadow, and the distance of the shadow from the vehicle is displayed.

11. The arrangement as claimed in claim 7, wherein the dark images are caused by one of a bridge, or a flyover comprising a shadow thrown onto the roadway in front of the vehicle.